Jabra Evolve2 65 Compatible Battery AHB300265 3.7V 380mAh

Jabra Evolve2 65 — 3.7V Li-Polymer Replacement Battery (AHB300265)

This 3.7V, 380mAh lithium-polymer cell replaces the original AHB300265 pack in the Jabra Evolve2 65 and Evolve 2 wireless headsets. It restores audio and DECT radio function when the original cell has degraded or stopped holding a charge. Capacity is 380mAh (1.41Wh) — matched to the original specification.

• Evolve2 65 and Evolve 2 fit: Both models use the same cell format, connector, and BMS handshake protocol. The 34.80 × 15.20 × 6.70mm footprint fits the headset housing without modification, and the BMS communicates directly with the base station charge circuit.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the Evolve2 65. The BMS negotiated correctly with the base station, accepted a full charge without fault flags, and delivered stable voltage under combined audio and DECT radio draw.
• First-cycle base station protocol: Place the headset in the base station and allow a complete charge cycle before making any calls. The Evolve2 65 base logs the new cell during that first cycle — until it does, talk-time estimates on the base display will be inaccurate.

Why the Evolve2 65 cuts out mid-call even with a new battery installed

The Evolve2 65 draws from the cell for both audio processing and the DECT radio simultaneously. Under that combined load, a cell sitting at storage voltage — not yet fully conditioned — can sag below the BMS cutoff threshold and trigger a shutdown. This is not a faulty cell. It happens because the pack has not completed its first full charge-discharge cycle in the base station. Run two or three full cycles through the base before extended use and the sag behaviour resolves.

Base station shows full charge but headset cuts off after a short time

When a replacement cell arrives at storage voltage (typically around 3.6–3.7V), the base station may report a full charge before the cell has actually reached capacity. The BMS handshake between the headset and base has not yet completed a calibration cycle, so the charge indicator is unreliable. Seat the headset in the base, leave it for a full uninterrupted charge cycle, then discharge fully through normal use. After two to three cycles the base display and actual cell capacity align.